培养基介质中 MBQA 对 TGB 菌的抑制机理及模型

为了深入探讨双季铵盐类化合物(MBQA)对于腐生菌(TGB)的抑制作用,用原子力显微镜、电子探针和扫描电子显微镜等测试方法研究了培养基中双季铵盐类化合物MBQA对腐生菌的抑制机理及模型.结果表明:MBQA能够在培养基中的碳钢金属表面优先吸附,形成完整致密的有机吸附膜,使细菌新陈代谢产生的产物难以到达金属基体表面;同时,MBQA使生物膜的沉积变得疏松,膜下硫酸盐还原菌的腐蚀也受到有效的抑制.     

基于Bandelets变换的EPMA图像融合

针对样品精密检测工作中影像数据复合处理不足的现状,提出以增加图像信息量为目的的多源影像融合分析方法。在分析电子探针微分析影像特性的基础上,结合新小波Bandelets变换在图像表示方面的自适应多尺度优点,给出利用Bandelets变换来完成EPMA图像快速融合的方法与实现过程,对融合结果进行比较与评价。仿真测试结果表明,该方法具有一定的实际参考价值。     

时效Sn-9Zn-3Bi/Cu钎焊接头的电子探针分析

用EPMA-1600型电子探针波谱分析了Sn-9Zn-3Bi／Cu钎焊接头在170℃时效1000h后的界面组织及其成分。结果表明，界面处存在三层化合物层。从基体铜侧起，依次为Cu-Sn化合物层、Cu-Zn化合物层和Sn-Cu化合物层。电子探针能够有效分析微观组织、成分的变化和扩散现象。     

Effect of Al additions in WC-(Cr1−xAlx)N coatings on the corrosion resistance of coated AISI D2 steel in a deaerated 3.5 wt.% NaCl solution

Multilayered WC-(Cr_1−xAl_x)N coatings were deposited on AISI D2 steel using cathodic arc ion plating (CAIP) process. Five kinds of WC-(Cr_1−xAl_x)N coatings were prepared: WC-Cr_0.6Al_0.4N, WC-Cr_0.57Al_0.43N, WC-Cr_0.53Al_0.47N, WC-Cr_0.48Al_0.52N and WC-Cr_0.45Al_0.55N. The Al concentration could be controlled by using evaporation source for Al targets and fixing the evaporation rate of the other metals (WC alloy and Cr). In this study, the corrosion behavior in deaerated 3.5 wt.% NaCl solution was investigated by electrochemical corrosion tests (potentiodynamic polarization test, galvanic corrosion test, electrochemical impedance spectroscopy (EIS)) and surface analyses (glow discharge optical emission spectroscopy, X-ray diffractometry, scratch adhesion test, scanning electron microscopy, electron probe micro-analyzer).

The results of potentiodynamic polarization test showed that the WC-Cr_0.48Al_0.52N coating with lower porosity exhibited the lower corrosion current density. The galvanic corrosion current between the coating and the substrate showed low values. In EIS measurements, the charge transfer resistance (R_ct) value of WC-Cr_0.48Al_0.52N coating only increased with the immersion time, when compared to the other coatings. It can be due to the corrosion products plugging the pores and increasing the pathway resistance.     

Isothermal section at 927℃ of Cr-Ni-Ti system

The isothermal section at 927℃ of the Cr-Ni-Ti system was established using a high-efficiency diffusion couple approach, supplemented with eight equilibrated alloys. The alloy compositions were selected on the basis of the experimental results from the diffusion couple. Both the diffusion couple specimens and the alloys were examined by means of optical microscopy, scanning electron microscopy, and electron probe microanalysis. No ternary compound is found at 927℃. The following five three-phase equilibria are well determined： TiNi3＋（Cr）＋（Ni）, TiNia＋（Cr）＋TiNi, TiNi＋（Cr）＋Cr2Ti, Ti2Ni＋Cr2Ti＋TiNi and Ti2Ni＋Cr2Ti＋（Ti）. The solubilities of Cr in NiTi2, NiTi, and Ni3Ti are determined to be 7.5%, 14.5% and 11.4% （molar percent）, respectively, α-Cr2Ti and β-Cr2Ti dissolve about 9.2% and 13.9% Ni （molar percent）, respectively.     

海水电解用金属氧化物阳极的失活机理

海水电解制氯用钛基金属氧化物阳极的等效电路可用LR5（QdlRct）（QfRf）来描述，上反映了阳极涂层复杂的微观结构，（QdlRct）对应电极／溶液体系的电化学特征，（QfRf）反映了涂层内表面／钛基体之间的物理阻抗。在阳极失效前后，Qdl和Rct没有发生突变，而Qf和Rf发生了突变，EIS谱图上发生明显的变化。SEM和EPMA分析表明，失活后表面还有一定的活性组分存在。阳极失活的主要原因是在钛基体和涂层之间形成了不导电的TiO2层，而阳极活性组分的电化学溶解和涂层的机械脱落不是阳极失活的主要原因，但对生成不导电TiO2有促进作用。     

Cationic substitution in tricalcium aluminate

Cubic and orthorhombic crystals of tricalcium aluminate doped with Na₂O, Fe₂O₃ and SiO₂ were prepared and examined using an electron probe microanalyzer. The cationic ratios based on six oxygen atoms were derived from the oxide compositions. These data, together with those in previous studies for clinker aluminates containing Mg²⁺ and K⁺, provided excellent correlations between Al+Fe and Si (Al+Fe=2.001−1.03Si) and Ca+Mg and Na+K+Si [Ca+Mg=3.006−0.51(Na+K+Si)]. The chemical variation that is constrained by these equations is well accounted for by the general formula (Na,K)_2x(Ca,Mg)_3−x−y[(Al,Fe)_1−ySi_y]₂O₆, where x is the amount of Ca substituted by Na and K (0≤x<0.158), and y is the amount of Al substituted by Si (0≤y<0.136). The crystal system changed from cubic to orthorhombic with increasing x value. The substitution of Si and Fe for Al extended the solid solution range of the orthorhombic phase to lower values of x, while its effect on the solid solution range of the cubic phase was reversed.     

虚拟企业伙伴选择中的多目标决策问题

在竞争，合作，动态的市场环境中，虚拟企业被认为是21世纪最有竞争力的企业运行模式，但如何选择合适的伙伴，则是虚拟企业能否组建成功的关键。在应用整数规划描述虚拟企业伙伴选择多目标决策模型的基础上，给出了支持伙伴选择的多目标决策工具与算法，并以实例说明该工具能有效支持虚拟企业伙伴的选择。     

GH4738合金高温扩散退火工艺

借助于Thermal-calc热力学软件计算了合金的平衡凝固相图,以此为依据制定了高温扩散退火处理的试验参数。利用OM和SEM观察了GH4738合金的铸态偏析状况,并用EPMA技术研究了合金铸态以及不同高温扩散退火制度下的元素偏析规律。结果表明,铸态合金中Ti元素偏析最为严重,高温扩散退火处理后Ti元素偏析得到明显改善,经1200 ℃×50 h的高温处理后效果最为显著,同时计算了残余偏析指数随温度的变化曲线,计算结果和试验结果基本吻合。     

涂覆层质量与电阻器失效的关系

利用电子显微镜分析技术对ＲＹ－２Ｗ－１５ｋΩ电阻器在电视机中失效原因进行了分析，对比用＃１、＃２绝缘漆涂覆层的电阻器表明，＃２涂层致密性差，微孔多，在贮放、使用中吸潮引起电阻膜腐蚀，导致电阻器失效。